The development of chondroprotective drugs for osteoarthritis has created a demand for noninvasively assessing therapeutic methods of treatment. We have used 23Na MRI at 4T to assess cartilage integrity in an in-vitro bovine model. Our degradation model consists of an intact bovine patella in which half of the patellar cartilage is degraded in trypsin while the other half serves as a control. 23Na images of these patella showed a significant decrease in signal intensity and changes in T1 and T2* values in the degraded side compared to control tissue. Our studies have also compared the efficacy of 23Na to 1H MRI for monitoring degenerative changes in cartilage. In our in-vitro model, signal intensities in the 23Na images showed greater differences between degraded and non-degraded cartilage than corresponding proton images. This suggests that 23Na may be more sensitive in monitoring cartilage degeneration. Currently, we are in the process of quantitating the degenerative changes observed by these methods.